This invention relates to a hand-held dry powder dispenser, and more particularly to such a dispenser which can accommodate a blister pack of several rupturable pillows containing dry powder to be dispensed for personal care use.
Dry powder dispensers are available for use in expelling especially pharmaceutical media to the respiratory tract, such as through the nose and throat. Some powder dispensers are adapted for a blister pack containing a plurality of metered power packets to be dispensed from rupturable pillows or compartments. A moveable spike or anvil is provided for rupturing the pillow upon manual movement of one section of the dispenser relative to another, whereupon the powder media is free to be expelled through a discharge path of the dispenser.
A known dispenser of the type characterized above is disclosed in U.S. Pat. No. 6,179,164 to Karl-Heinz Fuchs. There the powder dispenser comprises moveable and stationary parts relatively moveable along a central axis. This stationary part supports a blister pack containing powder filled blisters or pillows in a circular array, and the moveable part has a spike and a coaxial discharge nozzle such that upon rotary shifting movement of one of the pillows in alignment with the spike end, inward shifting movement of the manual part ruptures the pillow and exposes the powder to the discharge nozzle. The moveable and stationary parts together include air piston and cylinder units, such that upon relative movement of the parts together air under pressure is forced through a one-way valve in the stationary part for directing the pressurized air to the exposed powder causing it to be expelled out through the nozzle discharge.
The prior art powder dispenser as aforedescribed is not without its drawbacks. For example, the air piston stroke is limited by the maximum spacing between the stationary and moveable parts, and the path of movement of the compressed air before it reaches the exposed powder is quite circuitous. For example, the path of the air is first axial, then outwardly radial and then again axial requiring an abrupt 90xc2x0 turn. Because of the short stroke and the circuitous nature of the air path, air under sufficient pressure is unavailable at each stroke for adequately and completely expelling the loose powder from the discharge nozzle. Besides, since only a foil backing of the pillow is ruptured for freeing the powder contents of the pillow, the likelihood of completely expelling the powder from its opened pillow by the movement of a circuitous and short stroke air path, is limited.
There is need to improve upon the known dry powder dispensers to ensure that the entirety of the measured media is expelled from the ruptured capsule in a manner which is efficient, effective, and economical.
It is therefore an object of the present invention to provide a dry powder dispenser of the type which accommodates a blister pack supporting measured quantities of a plurality of powder media, the blisters being ruptured one-at-a-time by a moving anvil with the freed powder media being forced out through the discharge by a burst of air under pressure.
To this end the dry powder dispenser according to the invention assures expelling of the entire contents of each of the capsules of the blister pack on incremental rupture thereof. The dispenser is structured such that the blister is completely emptied of its powder contents upon rupture by the anvil as the contents drop under gravity into a discharge passage at which time a puff of compressed air discharges the powder from the dispenser.
The dry powder dispenser of the invention includes a base supporting at least one medium reservoir having an hermetically sealed and openable dry powder containing chamber which aligns with the discharge opening in the base. A discharge passage in the base communicates with the discharge opening, and means are provided in the base for flow feeding a quantity of pressurized air along the discharge passage. A hinged lever on the base displaces the dry powder from its chamber, upon actuation thereof which sequentially activates the air feeding means.